Agentjayz, your videos will be online after we are gone. Your effort and work to make them will be watched for 100's of years (who knows). You will be teaching jet engine fundamentals to people well into the future so if you decide to make a new series of videos it will be an inspiration for many of people for years to come. People who have an interest in jet engines or engineering but maybe not have went to school for it. I know this Carpenter learned a lot about jet engines from you !!
A little late here - but YES!!! Please do a series - I spend a good chunk of my work days listening to your vids (and repeats) because I love your explanations, down-to-earth presentation and relatable personality, and reality checks (calling out ill-commenters haha). You are the absolute best presenter for Gas-generators/Turbine engines and encompassing topics; a ‘Basics Series’ put out by you would be the most understandable, and enjoyable material yet on the subject.
“What’s that?” That’s the ski jump. It actually improves flow efficiency since original PT6s didn’t have it. Not all of them do, but that’s what my PT6 instructor told me.
If I remember correctly that little ski jump is to keep the exhaust heat a bit deflected away from the reduction gearbox. It’s been 15 years since I’ve tested PT6s though.
I would agree that a series of videos going through this would be very helpful. As a former instructor in computer languages know how difficult it can be to relate complex (and often un-intuitive) concepts to people, but you have a knack for doing this in your videos. I can see such a series of videos being a great way to get these ideas across, especially to non-engineers - your videos work well because of the examples you use and the clear way you explain the concepts. Adding a series of videos would give folks a good resource that I haven't seen anywhere else. So I think it's a great idea to do this.
Yes, accurate terminology is a must. Please help me to be less ignorant. As a gas & diesel mechanic for 50+ years, it is nice to learn about this stuff!! Every video you do is an instructional video. Please continue with my education. I am ready to absorb.
Dude..I work as an A & P for a major airline out of LAX and your knowledge of the nuts and bolts of jet engines makes me look like a rookie. I wish you were closer so you could show me a few things. Hell, I'd work for free..
Yes, please do the videos on schooling. I would watch every one of them over and over. I think I have a good handle on the way the jet engines are made but you can never, NEVER have all the schooling that you need. At least for me. Thanks for bringing these videos to the viewers. I know it isn't easy and take a lot of your time. They would be very valuable to many people. I tell people about your RU-vid channel all he time. I hope they are subscribing. Thanks for all you do.
"The Basics" would be a brilliant series from one such as yourself. I would, however, like to be selfish and request that your ongoing maintenance, overhaul, testing, and occasional boat & bike content does not take a sideline.
I to, wish to be selfish and request that you continue adding sidetracked content. Your series on rebuilding those JBL speakers, I could not get enough of! It is your channel, do with it as you will. Your editorial decision"s are flawless...
Hello AgentJayZ, firstly many thanks for your very informative videos. I'm a big fan. I'm not sure if an actual PW engineer replied to your question as to the purpose of the protruding baffle at the exhaust duct stage of the PT6 engine. I'm only an electronics engineer but touched some aerodynamics when I was studying my renewable energy core modules specifically when doing the wind generation subjects. My take on the functionality of the horn shaped baffle on the exhaust duct of the PT6 is to act as a 1-way valve for when the engine is running at low speed and to potentially stop air current generated from the the propeller from pushing it's way into the engine and potentially overwhelming the airflow causing the engine to stall or surge.
Air will not flow into the exhaust, and if you look at any PT-6 installation, the exhaust ducts are pointing to the rear. (in the same direction as the airflow from the propeller). I appreciate your interest and the gesture.
I'll chip in to the "yes, please, would like those instructional videos" :-) I already enjoy and appreciate all your explanations very much, so those would be quite welcome as well.
Yes definitely, I admire your gift of being able to communicate in a way that is not only informative, but fun as well. I wait for your videos patiently. I hope you are doing well on the race track too. Nice bike. Thanks Jay, You are a gift .
I have learned more about this subject in this short time of this video than i have in the last few years of casual interest. To speak of such a complex subject in layman's terms indicates someone who masters the craft. Thankyou! I hope one day we get to see the Iroquois 116 run!
Easiest way to answer your question... YES!! MORE VIDEOS! If your ever uncertain the answer is ALWAYS MORE VIDEOS! ANYTHING YOUR WILLING TO TEACH WE THE INTERNET ARE WILLING TO LEARN!!! You deliver this stuff in such a clear and easy to understand way and unlike 95% of RU-vid videos you actually know what your talking about with experience and a shop full of examples to provide clarification. I'm a fixed wing guy just starting my rotary conversion in a 206 with a life long passion for this stuff. I try and soak up anything I can relating to these machines and engines we depend so heavily upon. Thank you!
Thank you for another excellent video. I've spent the past three years resurrecting a Rolls Royce Palouste, my first gas turbine engine. It's been a steep learning curve but I'm almost there. It has fought me every step of the way but I've proved my hard work isn't in vain. It's now a runner! I've also built a bespoke control panel within a 2u flight case and my partner is constructing a trailer clad in mirror finish stainless. I hope to exhibit at a public event next summer. If anybody out there is considering a similar project my advice is take your time and do it properly. Oh and if anybody has a spare air bleed valve for a Palouste, please get in touch ☺thanks JayZ, Charlotte.
@@AgentJayZ I promise I will, but it's going to be a while until I run it again. And, I'd like to showcase it when I've finished the job and it's on its trailer. I do have a video of the first run but I ran it rich without instrumentation, I know what you're thinking but I just needed to hear it. The whole village heard it... One guy came looking for a plane! I've also documented the project with lots of photographs. The engine was a Valentine's present, the best present ever. It's not one project but many and I've still much to do before its first public showing next July.
I’m really glad you are doing these videos. Hopefully it will instruct and educate some of these newer turbine engine mechanics. We’ve been getting some really interesting people wanting to in our test cells.
Quick clarification all of the new engines (non clamshell) do NOT send any core air in reverse. Only Bypass air is reversed. This was done to let the heat expansion part of the engine be unrestricted and also not send hot air back in front of the plane or allowed to get recirculated.
About the combustion chamber pressure which stay constant. Turbine engines use the Brayton cycle. Piston engines use the Otto cycle. The key aspect in the Brayton cycle is the temperature increase and volume expansion at constant pressure.
Yes, I vote to see you develop an online course as you described. I'd love to watch and learn from it. And I'm with you on the importance of precise terminology. Maybe a chapter just for that, or maybe sprinkled throughout all chapters. As analogy: A friend of mine rubbed my nose in racing sail boats for several years. First lesson in parlance--"Those are not ropes. A rope with a purpose is a Line". Then, during a race one day, a second generation master sailmaker aboard looked at me and said "Hey Tom, could you tighten the Boom Vang". I had no idea what that was, I looked around, there seemed to be 20 lines, pulleys and cleats. I learned what it was. Sailboats have their own specific terminology. Boom Vang, Backstay, Forestay, Downhaul, Halyard, Foredeck, Stanchion, Rail meat, etc. Very specific and important terms for communications aboard. Jet engines the same I think.
Thanks for getting me through A&P school! :) Would love to see a series of the basics, and hopefully more series on specific systems after that! The explanation with the cutaway in this video was extremely helpful
Basics video series is a great Idea. Hopefully they would solve at least some of the misconceptions and misunderstanding some people have. Better for them, better for you. I enjoy all your content and have learned a lot, I am just a retired guy but I love learning about machines. Thanks for doing what you do. PS. Who doesn't love afterburners.
All these different types of engines is complicated. I find it fascinating. I appreciate you taking the time to explain them. I need to rewatch this one. Lol. Thank you for sharing your knowledge.
Yes I would appreciate a set of instructional videos. Having the correct definitions of terms makes communication more efficient. You have made many hours of video so sifting through them all to find one fact makes me wish you had some basic instructional videos, and now you are offering to do that. Great!
About swapping plug wires on a Harley. I don't know about the newer ignitions, but my 78 engine fires both spark plugs at the same time. 1 into the compression stroke and the other into the exhaust stroke . Kits are available to make them single fire, but I leave well enough alone! And I'm all for the educational videos. Keep up the great work. PJC
I love all your videos, the more technical the better. I realize you can lose a lot of people with the actual details but I love them. I like the idea of you making a series of technical videos, or basics, either way, please keep them coming.
Extremely cool videos!! Thanks for sharing your knowledge, I currently fly at a regional carrier, using the corona time off to study more maintenance with your videos!!
PLEASE make the "basics" course. I would love to have your videos to reference when teaching people about how jet engines /actually/ work. You'd explain it perfectly.
Definitely do the Basic/Foundations video series! There is something like that on YT for diesel engines and it's helped me work on my truck and appreciate its design.
Been waiting for a new episode, great one thanks! I think Frank Whittle's first jet and also the RR version, Welland, had a reverse flow, apparently, Whittle was worried that a long shaft connecting the compressor and turbine would cause "whirling" issues. Another classic, excellent engine is Bristol Proteus, also used for power generation!
I'm in the aviation industry, but I think you've covered in great detail how a turbine engine works. You have entire video series where you disassemble and re-assemble entire engines, and describe the individual components in detail (your excellent fuel nozzle video is an example). You have numerous QA videos where you explain concepts and answer questions. If you want to do a mini-tutorial series I say go ahead. I don't think it's necessary for anybody that wants to spend time in your channel. The answer is there somewhere.
Wow! I didn't expect you'd make a whole video answering my question... Thank you very much! All I know about turbine engines I've learnt from your channel. So when I came face-to-face with an industrial gas generator that was a bit different than what I've seen I was perplexed. Thank you for pointing out my misconception and enriching my knowledge! Of course a series of instructional videos would be greatly appreciated, although it would be a good idea if I'd get one of those books you recommended some time ago.
It's a good question, if all you know is the engines that Jay shows. Working around airplanes for a living I knew all about the PT-6 but didn't know about all the other older designs, with direction changes.
The Garrett ATF3 used by the coast guard's HU-25 is an interesting beast with lots of airflow reversals, the HP and LP compressors are on opposite sides of the hot section.
Oh by the way, my misunderstanding was that those turbine blades are mounted loose for heat expansion. You told me in one of the vids that it's actually for vibration damping. Thanks for all this info. I've always loved fast stuff and big loud engines. I'd buy a Saturn 5 if i had a big enough back yard....
Cool channel. I subscribed! I use to overhaul the J52's , T-56, j-79. I also did oil analysis.. I miss the work, but I got injured and that was the end of that!
Thx AgentZ for your dedication to your YT channel viewers you provide a great resource to them and myself. I was lucky to have had training on jet engines in USN J79/LM1500 as Engineman + A&P training J47 and as electrical power power plant operator. 8 J75 powered 180mw peaker unit. I believe your videos are spot on for training those that are willing to learn but some people just want to or for other reasons (I won't get into here) do not do their do diligence in researching your extensive YT video library before asking ?S. As I learned in the military if you want to learn you've got to earn it i.e.(Study) to gain/retain knowledge .FWIW When you were discussing igniters in jet engines you mentioned all jet engines having them which is incorrect as the PW J58 in the blackbirds only used a hypergolic chemical called TEB that would ignite the extremely high flash point JP7 fuel which would not ignite with conventional spark igniters but you wouldn't have a need to know and I haven't seen you service one of those 35,000# thrust engines yet. Keep 'em coming JayZ
Yes please, more videos and explanation, we can all learn something new or add to our current knowledge for sure. None of us knows it all. I have worked on the edges of engine production for some a tad under 40 years in the Quality Assurance aspects of making the Titanium fan blade blanks initially for the for the RB211 E4, then all the way up to the Trent 1000 for RR and with the V2500 and the PW7000 thrown in for good measure. Then thrown in just to make things interesting, condenser tubes for nuclear power stations, control rods, nuclear core and canning materials, surgical and other assorted chemical applications in Zirconium, Niobium, Hafnium to name but a few.
That is so cool of you to give a shout out to the puerto focal family. IMO, I think both sides of the flag are backside and frontside. The difference in how you hang the flag is telling of which way the wind is flowing. Notice on Aircraft’s tail or fuselage, and patches on soldiers arms (no pun intended with soldiers and arms😉). But, you understand what I am saying. When you raise a flag up a pole, you would see the different sides of the flag depending on the wind direction. Aircraft are flying into the wind, thus, on the starboard side, it appears backward, as is with soldiers arms. They depict advancement of the soldier and not retreat. ✌️🤙
Also, if you see the GE industrial gas turbines (frame -5/9 E/7E etc), you will find them all "reverse flow configured". If you read the GE manual, it says , it is only for "cooling", nothing else..... Thanks for your excellent explanation.
Yes! I didn't know a thing about jet engines until I started watching your videos. I think making a course on the basics would actually be the best thing you can do for your chanel.
it is good to see you still around Jay and crew, great vids as usual. B) I do agree with "what's that thing called?". I do even have difficulty at times with the differences between guide vanes vs stator vanes in non-jet things (computer fans). I've even seen a few diagrams that refer to variable stator vanes as (VGV's, variable guide vanes in the compressor of a jet engine). I do know that an Inlet Guide Vane or strut is a thing in front of the compressor, I did think at one time that the rest of the "guide vanes" were supposed to be in the turbine after the combustor cans, to guide the air at the turbine blades at a good angle for the turbine to work 'well'. It's an interesting topic to me, as I think some outside of the jet realm, get confused as to if a computer fan only has air straighteners, or if them 'things' actually improve the effectiveness of the fan to move air. I can see it going both ways depending on how well the fan was engineered, or if it was just a 'designer' RGB bling fan for looks only, lol. 18:20, cone behind the center of the turbine on the engine exhaust, I have fused with similar things using easter eggs glued to the back of computer fan motors to get more consistent flow through a radiator (behind the fan motor), with varying success. for exactly the reason you describe, transitioning the donut of airflow to more of a full disc of moving air through the radiator. B)
May I offer a "quick-and-dirty" answer that DOES NOT want to replace Jay's suggestion? I speak only for AIRCRAFT installations, not for the fixed ground installations on which I have never worked. Igniters are always powered during startup, of course. Very often, especially on commercial airplanes, igniters are also operated during takeoff, final approach, and when rain/heavy rain is encountered. Such mode of operation is called "continuous relight" or "continuous ignition", and is intended to recover as fast as possible should a flameout occur.
Thanks for the video...I always wondered why PT-6 engines had exhaust pipes at the front . Modules detailing jet engine operation would be very cool...
It would be a great idea to do those tutorials. Look forward to watching. I'm currently going through your videos. I almost got the job as a Propulsion Tech. with the RAF but they failed me on my medical due to a few short fingers lol. Strange that they let me do all the tests and I passed before halting me at the last hurdle. Oh well. Does not stop me from using my hands, including riding (and maintaining) very fast big sportsbikes. Did some track days and Isle of man TT course. I know you would like to hear that. Nice videos. ))))
Good video. I test the industrial version of the J75 (GG4) regularly. Good, simple, and dependable engine. But today's test didn't go too well. High N2 vibes in the diffuser and stalls on decel. Back to the shop it goes.
In a number of you previous videos I caught snippets of the test cell redesign and update. You mentioned how the test bed was lowered, made in a modular fashion, and the propane metering valve moved to the front wall. From the excavation pix it looks like a larger concrete block was poured and coupled into the new yellow bed frame. I don't think I found your explanation of the reason for the redesign. To handle more thrust? To lower the resonant frequency of the stand? Please excuse my need for why ... it seems to be how I was made... :-)
Yes to an on-line educational set of videos. I have watched all your videos from #1, so I know you have covered it all. But, obviously some just come up with questions based on too little information. Anyhow, a refresher course for me wouldn't hurt as I don't claim total recall. Meanwhile. keep up with the good work. I know more about the internal workings of a turbojet engine than my 734 Captain son.
Hi Jay, I’m building electric dynamic turbine machines so finding your coming in handy with your explanations. Here Goes, that Pratt Whitney forward facing exhaust with as you described a “horn” shape at its exit, TESLA as in Mr designed a “tesla valve” to aid in the attenuation or cause a benefit to a fluid flow. Rus
Thrust reversers: Blocker doors and cascade vanes (I think that's the terminology you were looking for...) There is also the bucket type TR's (commonly seen on DC9/MD80's.) EXCELLENT EXCELLENT EXCELLENT VIDEO!!!! I agree 100000% on using proper terminology... Trying to correspond with someone who doesn't know proper terminology... are they talking about a propeller, or the aileron? "You know, that flappy thing that moves!" Uhm... no, I have no clue what you're talking about. On the PT6, that little ramp in the exhaust duct--- that creates a venturi effect, which draws cooling air in through the oil cooler while the aircraft is at low speed or even stopped.
AgentJayZed, yes, yes you should (do 4 beginners modules). Why, when the information is already out there? Well, because I"m technical and have learned more here than from any other source. You, sir, are thorough, in a superficial world. Carry on...
Ha. The lovely "smokless" Garret TFE-731. First time I've heard that phrase used in decades. The company I was flying for was an early adopter, and as it happened, was the only time that I ever "lost" an engine. The geared turbofan ingested it's gears on first power reduction after take off. It continued running until we made it back to our departure point. Shortest flight that DA-10 ever took.
We have Derwent and a sectioned Welland here. The radial compressor draws air from the front and rear of the engine before pushing it into an annular ring which feeds the combustors. A single stage HP turbine behind drives the compressor (at the front) directly. So lots of direction changes but very few obstacles to the gas flow. I used to think it must be very inefficient, now I know better, thanks A J
When you said you got to use the right terms I was thinking this is exactly the same issue with computer software engineering. In software, there are thousands of terms which if you don't use correctly it's very hard for others specially seniors (cause they know many more terms) to understand you. Thank you for posting these videos, and about the basics of jet engines, I don't really know what you want to cover in those episodes but if it's about the terms that you mentioned in this video I think you should do it and I bet you already did some of them. I'm also interested in more scientific explanations of some of the parts. Jet engines are extremely hard to understand so maybe adding a little bit of physics and formulas to the videos might help people like me to understand the details better.
Hey Mr agentjayz. I'm from and how. Your teaching is the best I've ever seen. You are very clean in teaching about air and sea machine. Bring a course online online aircraft and marine is the best idea,which is feel like knowledge protein. Well Mr agentjazy in the course I'll like if u bring a course on building marine & airship. Thank you
Yes on the course, but also, not just how they each section works, but if you could include lots of stuff about misconceptions and mis-intuitions, and what the design variables are (ie how things are changed to tailor the engine), this would Really differentiate the course/lessons from other informational videos that view like encyclopedia blurbs. Thanks! love the videos
Moving air has some momentum which needs to change direction and there is a small inefficiency in this (it will heat the tube walls) , but most of the energy is in the compression of the air (like a spring). Remember that individual air molecules are travelling at a thousand miles an hour in random directions anyway no matter what their overall flow is.
The two cones in the exhaust chamber of that first engine may be using a small gap to evacuate something in front of it. Exhaust passing another open tube or chamber can create a low pressure zone. That is how headers on a car are more efficient than manifolds, actually makes the other tubes low pressure and helps vac the other cylinders.
I would like to see you do an explanation on SR-71 engine unstarts as well as use of the engine spikes. Reducing speed of airflow to below the speed of sound while the plane is at mach 2 or 3 is also something that interests me. Thanks for your videos.
